From bfa0bc98b7b37ec693585b424e86a49f22e149a3 Mon Sep 17 00:00:00 2001
From: Conduitry <git@chor.date>
Date: Fri, 2 Aug 2019 16:47:26 -0400
Subject: [PATCH] preserve async/generator-ness of hoisted function expressions
 (#3179)

---
 src/compiler/compile/nodes/shared/Expression.ts      | 2 +-
 test/runtime/samples/event-handler-async/_config.js  | 5 +++++
 test/runtime/samples/event-handler-async/main.svelte | 1 +
 3 files changed, 7 insertions(+), 1 deletion(-)
 create mode 100644 test/runtime/samples/event-handler-async/_config.js
 create mode 100644 test/runtime/samples/event-handler-async/main.svelte

diff --git a/src/compiler/compile/nodes/shared/Expression.ts b/src/compiler/compile/nodes/shared/Expression.ts
index 3702800c7ba9..938cd8433fce 100644
--- a/src/compiler/compile/nodes/shared/Expression.ts
+++ b/src/compiler/compile/nodes/shared/Expression.ts
@@ -363,7 +363,7 @@ export default class Expression {
 					}
 
 					const fn = deindent`
-						function ${name}(${args.join(', ')}) ${body}
+						${node.async && 'async '}function${node.generator && '*'} ${name}(${args.join(', ')}) ${body}
 					`;
 
 					if (dependencies.size === 0 && contextual_dependencies.size === 0) {
diff --git a/test/runtime/samples/event-handler-async/_config.js b/test/runtime/samples/event-handler-async/_config.js
new file mode 100644
index 000000000000..fab4d998b605
--- /dev/null
+++ b/test/runtime/samples/event-handler-async/_config.js
@@ -0,0 +1,5 @@
+export default {
+	html: `
+		<button>nothing</button>
+	`,
+};
diff --git a/test/runtime/samples/event-handler-async/main.svelte b/test/runtime/samples/event-handler-async/main.svelte
new file mode 100644
index 000000000000..b22a6af92ed7
--- /dev/null
+++ b/test/runtime/samples/event-handler-async/main.svelte
@@ -0,0 +1 @@
+<button on:click={async () => { await null; }}>nothing</button>